The striker was told he's not wanted at Chelsea in a text from boss Antonio Conte

Ricardo Cardoso also revealed that his client's hands are tied because the "unfair behaviour of Antonio Conte makes it impossible to return to the English club".

Cardoso told Spanish publication EFE: "We are going to use all legal mechanisms to hold Chelsea accountable for his behavior, making it possible for Diego Costa to leave.

"We will formally request the transfer request.

"When he was in the service of the Spanish team [for the friendly against Colombia on June 7] and before travelling to Brazil to enjoy holidays was dismissed from Chelsea by SMS by coach Antonio Conte."

Conte has continually refuted that claim, making it perfectly clear that Costa knew in January that his time at the Blues was coming to the end over the summer.

Conte said: "I don’t like to talk about players who are not here but the only thing I can tell you [is that] in January, the Costa situation was very clear, for the club for him and his agent.